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Eosinophils present in the duodenal mucosa of children with dyspepsia are activated in a significant proportion of patients, even in those with normal eosinophil counts. The degree of degranulation is similar to that seen in other conditions where eosinophils have a pathogenic role.

Purpose-To illustrate the feasibility of using hyperpolarized helium MRI (HPH-MRI) to obtain functional information which may assist in improving conformal avoidance of ventilating lung tissue during thoracic radiotherapy.Methods and Materials-HPH-MRI images were obtained from a volunteer patient. These images were first fused with a proton density weighted (PD w ) MRI to provide corresponding anatomic detail, then with the treatment planning CT of a patient from our treatment planning database who possessed equivalent thoracic dimensions. An optimized treatment plan was then generated using the TomoTherapy TPS, designating the HPH enhancing regions as Ventilation Volume (VV). A dose volume histogram compares the dosimetry of the lungs as a paired organ, the VV, and the lungs minus the VV. The clinical consequence of these changes were estimated using a bio-effect model, the parallel architecture model or local damage (f dam ) model. Model parameters were chosen from published studies linking the incidence of grade 3+ pneumonitis with dose and volume irradiated.Results-For two hypothetical treatment plans of 60 Gy in 30 fractions delivered to a right upper lobe lung mass, one utilizing and one ignoring the Ventilation Volume as an avoidance structure, the NTD mean values for the lung subvolumes were as follows: lungs=12.5 Gy 3 vs 13.52 Gy 3 , Ventilation Volume=9.94 Gy 3 vs 13.95 Gy 3 , and lungs minus ventilation volume= 16.69 Gy 3 vs 19.16 Gy 3 . Using the f dam values generated from these plans, one would predict a reduction of the incidence of Grade 3+ radiation pneumonitis from 12% to 4% when compared with a conventionally optimized plan.Conclusion-The use of HPH-MRI to identify ventilated lung subvolumes is feasible, and has the potential to be incorporated into conformal avoidance treatment planning paradigms. A prospective clinical study evaluating this imaging technique is being developed.

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SummaryAmylase activity was found in saliva from 13 infants, 26-42 wk corrected gestational age. The levels of salivary amylase activity increased with advancing age. In 10 infants, 31-38 wk corrected gestational age (estimated gestational age in wk plus age in wk after birth), gastric aspirates collected before a feeding and sequentially at 30-min intervals after two consecutive feedi n g~ were analyzed for amylase activity and pH. Two different postprandial patterns were obtained. For six of the 10 infants, both the pH and amylase activities of their gastric aspirates showed a distinct maxima at about 60 min after a feeding and a minima at 180 min just before the second feeding. In the remaining four infants, the pHs of their gastric aspirates remained relatively high (5.0-6.0) for the entire postprandial period. In these infants, there was a persistently high level of the amylase activity. In all 10 infants, amylase activity was found in their gastric aspirate samples when the pH was above 3.0. Comparison of the amylase in the gastric aspirate with purified pancreatic and salivary amylases by polyacrylamide gel electrophoresis showed that the amylase in the gastric aspirate has an electrophoretic mobility similar to that of salivary amylase, which suggests a salivary origin. This study supports the possibility that salivary amylase could enter the stomach and retain a significant amount of its activity in premature infants.Starch and glucose polymers are given in some formulas to infants very early in life to accommodate the increased caloric demands. Clinical intolerance to glucose polymers has not been examined sufficiently. Pancreatic amylase is the key enzyme in hydrolysis of glucose polymers. Recognition of intolerance to glucose polymers has been rare in spite of the lack of pancreatic amylase in the duodenal fluids of young infants. In part, this can be due to the existence of alternate pathways with auxiliary enzymes for the hydrolysis of glucose polymers during the physiologic deficiency of pancreatic amylase. The auxiliary enzymes include: salivary amylase, small intestinal brush border glucoamylase and mammary amylase in the breast-fed infant. We have shown that glucoamylase reaches levels similar to those of older children at 1 month of age (13). Two studies have noted the presence of a-amylase in preterm and in term human milk. The ability of milk amylase to survive the gastric environment has been examined and its physiologic importance in the young infant discussed ( 1 1, 16). Recently, we also reported an investigation on the possible role of ingested mammary amylase in the hydrolysis of glucose polymers (1 0). Salivary amylase has been shown to be present in infancy and to reach adult levels much earlier than pancreatic amylase (I, 4, 5, 15, 2 1, 28). The level of salivary amylase in premature infants is however not known. In this study we determined whether the salivary amylase was present and active in gastric fluids during feeding. MATERIALS AND METHODSSubjects. The group of prematures inc...